.web-message{
  position: fixed;
    z-index: 1002;
    left: 0;
    display: block;
    word-break: break-all;
    padding: 10px 20px;
    opacity: 0;
    max-width: 90%;
    background: rgba(0,0,0,.8);
    color: #fff;
    font-size: 14px;
    line-height: 18px;
    text-align: center;
    border-radius: 3px;
    overflow: hidden;
    top: 50%;
    margin-top: -50px;
    /* 写死 */
    margin-left: 56px;
    -webkit-box-sizing: border-box;
    box-sizing: border-box;
    -webkit-tap-highlight-color: rgba(255,255,255,0);
    -webkit-transform: translateZ(0);
    -webkit-user-select: none;
    -webkit-user-drag: none;
    -webkit-animation-duration: 3s;
    -webkit-animation-timing-function: ease;
    -webkit-animation-fill-mode: both;
    -webkit-transform: translateY(0px);
    -webkit-transform: translateY(0px);
    -webkit-transform: translateY(-10000px);
}
.show-message{
  animation-name: showMessages;
}

@-webkit-keyframes showMessages {
  0% {
    opacity: 0;
    -webkit-transform: translateY(20px)
  }
  20% {
    opacity: 1;
    -webkit-transform: translateY(0)
  }
  80% {
    opacity: 1;
    -webkit-transform: translateY(0)
  }
  98% {
    opacity: .1;
    -webkit-transform: translateY(-20px)
  }
  100% {
    opacity: 0;
    -webkit-transform: translateY(-10000px)
  }
}